1. Field of the Disclosure
The disclosure relates generally to apparatus and methods for control of fluid flow from subterranean formations into a production string in a wellbore.
2. Description of the Related Art
Hydrocarbons such as oil and gas are recovered from a subterranean formation using a well or wellbore drilled into the formation. In some cases the wellbore is completed by placing a casing along the wellbore length and perforating the casing adjacent each production zone (hydrocarbon bearing zone) to extract fluids (such as oil and gas) from the associated a production zone. In other cases, the wellbore may be open hole, i.e. no casing. One or more inflow control devices are placed in the wellbore to control the flow of fluids into the wellbore. These flow control devices and production zones are generally separated by packers installed between them. Fluid from each production zone entering the wellbore is drawn into a tubular that runs to the surface. It is desirable to have a substantially even flow of fluid along the production zone. It is also desirable adjust the flow control devices so that unwanted fluids, such as water or gas, are not produced or produced in reduced amounts from the affected zones.
Horizontal wellbores often are completed with several inflow control devices placed spaced apart along the length of the horizontal section. Formation fluid often contains a layer of oil, a layer of water below the oil and a layer of gas above the oil. The horizontal wellbore is typically placed above the water layer. The boundary layers of oil, water and gas may not be even along the entire length of the horizontal well. Also, certain properties of the formation, such as porosity and permeability, may not be the same along the length of the well. Therefore, oil between the formation and the wellbore may not flow evenly through the various inflow control devices. For production wellbores, it is desirable to have a relatively even flow of the oil into the wellbore and also to inhibit the flow of water and gas through each inflow control device. Passive inflow control devices are commonly used to control flow into the wellbore. Such inflow control devices are set at the surface for a specific flow rate and then installed in the production string, which is then conveyed and installed in the wellbore. Such pre-set passive flow control devices are not designed or configured for downhole adjustments. After the well has been in production, a wireline tool is periodically conveyed into the production string to determine one or more properties of the fluid, wellbore or the formation. If it is determined that the flow of the fluid from particular flow control devices needs adjustment, such as because a particular zone has started producing an undesirable fluid, such as water or gas, or the inflow control device has clogged or deteriorated and the current setting is not adequate, etc. To change the flow rate through such passive inflow control devices, the production string is pulled out to adjust or replace the flow control devices. Such methods are very expensive and time consuming.
The disclosure herein provides improved apparatus and methods for determining one or more properties of interest downhole and adjusting flow control devices without removing the production string from the wellbore.